Numerical Analysis of Sunroof Buffeting

Noise computations are carried out for sunroof opening in automotives at a resonating speed. First, the behavior of baseline opening shape is analyzed through frequency spectrum obtained from acoustic analysis. Then the opening shape is changed to reduce the sound pressure level of buffeting noise. The analysis with new shape is able to reduce the Noise dB levels up to 5dB. Commercial software, Fluent, is used to compute the turbulent flow field. Large-Eddy Simulation is used for better prediction of fluctuating components. Acoustic results obtained from Ffowcs-Williams and Hawkings equations are well compared with other's work.